You need more ram, and it looks like you purchased a budget gpu. Mine is a 670 and looking at benchmarks it looks like that beats yours soundly in all areas. Don't always assume higher numbers = better.
But don't think you need some $500 gpu or anything. My 670 plays all current games still great.
But you should upgrade your ram for sure. Just spend like $60 and get a couple 8 gig sticks. You may not need 16 gigs total, but for the price why not. Ram is cheap.